volcanic glass

Volcanic glass is a natural, non-crystalline material formed when magma cools rapidly after an eruption, preventing crystals from developing. This quick cooling preserves an amorphous structure, creating a smooth, glassy appearance similar to human-made glass. Common types include obsidian, which is dark and shiny, and pumice, which is porous and lightweight. Volcanic glass is often sharp and durable, making it useful for tools historically, and it provides valuable information about volcanic activity and magma composition. Its unique properties result from rapid cooling that halts crystal growth, resulting in a solid that is both aesthetically intriguing and scientifically significant.